The number of factory installed automotive air conditioning systems is increasing in these modern times. A condenser in the air conditioning system is generally disposed forward of a radiator since the temperature of a fluid in the condenser can become higher than that of a fluid in the radiator.
However, since the configuration of the condenser is different from that of the radiator as shown in FIGS. 1 and 2, the condenser and the radiator are manufactured during separate production processes, respectively, thereby increasing production costs. In addition, installing the condenser and the radiator in the automobile is also done separately, and it takes much time to attach them thereto.
Accordingly, it has been proposed in the prior art to use a heat exchanger in an automotive air conditioning system which functions as a condenser and a radiator as disclosed in Japanese patent application Laid-open Gazette No. 63-91488 and Japanese Utility Model Laid-open Gazette No. 63-74970. These prior art heat exchangers include a first core for a condenser and a second core for a radiator, which are aligned vertically in series. Therefore, it is necessary to enlarge the plane area thereof to maintain the same effective area for heat exchange as in a conventional condenser and radiator. This increased planar area creates difficulty during installation in an automobile engine compartment.